1. Field of the Invention
The present invention relates to a method of producing an optical film laminate.
2. Description of the Related Art
A polarizing plate is placed on each of both sides of a liquid crystal cell of a liquid crystal display apparatus, which is a typical image display apparatus, the placement being attributable to an image-forming mode of the apparatus. The following method has been known as a method of producing the polarizing plate (for example, Japanese Patent Application Laid-open No. Hei 11-179871). A protective film is placed on each of both sides of a polarizer, and then the protective films are attached to both sides of the polarizer by continuously passing the polarizer and the protective films through a pair of rolls while supplying an adhesive to a gap between the polarizer and each of the protective films.
By the way, in recent years, in association with a demand for thinning of the image display apparatus, there has been required a technology with which an optical film laminate having a thin polarizing film much thinner than such polarizer as described above can be industrially produced. For example, the following method has been proposed as a method of producing such optical film laminate (for example, Japanese Patent Application Laid-open No. 2000-338329). A laminate having a resin substrate and a polyvinyl alcohol (PVA)-based resin layer is stretched, and then a polarizing element layer is produced by subjecting the laminate to a dyeing treatment. After that, a protective film is attached to the polarizing element layer side of the laminate, the resin substrate is peeled, and another protective film is attached to the surface from which the resin substrate has been peeled. In such production method, the protective films need to be sequentially attached. Accordingly, in some cases, undesired curling occurs in an optical film laminate to be obtained and inconveniences (such as air bubbles and wrinkles) occur when the optical film laminate is attached to an optical cell such as a liquid crystal cell later. In particular, the problem tends to be additionally remarkable when one of the protective films also serves as an optical compensation film or an antireflection retardation film (typically a λ/4 plate) for thinning the optical film laminate.